set the value of nested obj at a given key-path, and then returns the object back.

import { assertEquals } from "jsr:@std/assert"

const data = { kill: { your: { self: [0, 1, { 0: 0, 1: { noice: "YAHAHA", 0: "you found me!" } }] } } } as const

// weakly typed variant
// note: adding `as const` will not make it strongly typed because of a limitation/bug in `KeyPathsOf`
const keypath_to_yahaha = ["kill", "your", "self", 2, 1, "noice"]
setKeyPath(data, keypath_to_yahaha, "YEEEE")

assertEquals(getKeyPath(data, keypath_to_yahaha), "YEEEE")

// strongly typed variant
const strong_keypath_to_yahaha: ["kill", "your", "self", 2, 1, "noice"] = ["kill", "your", "self", 2, 1, "noice"]
// @ts-ignore: since `data` is declared as `const`, we cannot technically assign the value `"YOSHIII"` to the original `"YAHAHA"`.
setKeyPath(data, strong_keypath_to_yahaha, "YOSHIII")

assertEquals(getKeyPath(data, strong_keypath_to_yahaha), "YOSHIII")